Newby with CAT 305.5E2 (not CR) -- I think the tracks are toast. Do I need new sprockets?

[Baxsie]

(sorry for all the posts - this forum limits to 4 images per post)

I had been starting to wonder if the tensioner on this idler was working OK. When I exposed the end of the cylinder, there was a blob of grease that had pushed out of the seal. Not to worry, it gets worse! The piston is corroded badly:



Maybe this tractor was used to excavate some of the layers of Dante's Hell?

It looks like grease has blown past the seal - I assume after the seal was damaged by the rust:



That looks like grease, but it is the hard plastic or metal of the seal.

The piston (353-5584) is available for $175. That and a couple seals (120-4664 $17, 095-1604 $4 and 095-1794 backer ring $14) should put it right.

I wonder if I could source a chunk of polished rod instead of the CAT piston.

 

[Baxsie]

With the track out of the way, I got some photos of the rollers:





The "flats" are pretty concave. I checked rotation for all the rollers. They turn and are not loose so I am not going to touch them.

 

[Baxsie]

Looking at the idler plate that was missing the bolts, here is what the CAT part looks like (thanks random internet photos):



The plate in mine has a second part welded to the back:



What looks like a depression is actually a hole, filled with dirt. I wonder what they were thinking?

 

[Nige]

I cleaned the bolts, holes and mounting faces. I reinstalled the bolts with generous anti-seize.

I have a question: Is there a torque specified for these bolts? They are M14x2 by 40mm grade 10.9.

As a first guess, I put them at 100 ft-lbs.

The spec is 120 ± 22 lb ft but with Blue Loctite 242 applied to the bolt threads, not anti-seize.

 

[Nige]

The "flats" are pretty concave. I checked rotation for all the rollers. They turn and are not loose so I am not going to touch them.

The wear surfaces on those track rollers are farked. You do not want to be running new track links up against those rollers, at least not IMHO.

 

[Nige]

wire brushed the head to find the grade. Not from this hemisphere:

They are 10.9 M12 x 1.75 pitch x 50mm. Cat P/N 8T-4194
The washers are somewhat special if the P/N 219-3939 is anything to go by. They are 21.9 OD x 12.2 ID x 1.6mm thick.

 

[Nige]

The plate in mine has a second part welded to the back:

That is correct. The Parts Manual illustration shows it. You should take note of the orientation of the stop on the plate and reinstall it the same way that it came out.

I bet that "random block" was installed by someone because the track tensioner had run out of movement and the track were too loose. The other option apart from replacing the tracks would be to remove a link.

 

[BC Placer gold]

Those rollers show extreme wear…

Hate to say it, but I would change them all while the tracks are off. I would be curious if those are original Cat parts or perhaps “cheap” aftermarket.

Would take a lot of machine hours/walking to show that degree of wear—also (perhaps) very abrasive working environment?

Good luck, you are making progress!

 

[HarleyHappy]

Unfortunately I also am in agreement. Replacing the tracks and pads and sprockets and not replacing those rollers, is not very helpful.

 

[oarwhat]

With that much wear on an excavator track it has to have major hours on the machine. Nige can the hours be changed? I'm sure someone has figured out how.

 

[Nige]

With that much wear on an excavator track it has to have major hours on the machine. Nige can the hours be changed? I'm sure someone has figured out how.

On something of this size class I have no idea TBH. On the larger machines it's theorectically not possible to "clock" hours but there are ways & ways around it.

I think the record of operating hours on this machine must only be maintained by the hour meter (#2) located under the seat. I see no other electronic controls on the machine, at least as I understand them, with an onboard memory capable of recording such data. It could be nothing more sinister than the hourmeter gave up and someone fitted a new one, then conveniently omitted to keep a record of how many hours were on the previous meter when it was replaced.

 

[Vetech63]

I don't trust hour meters. I get the hours registered on the ecu

 

[Nige]

I don't trust hour meters. I get the hours registered on the ecu

This machine don't got one.........

 

[HarleyHappy]

I trust my hour meters because they are so high, nobody wants them. lol
They all do work properly though.

 

[BC Placer gold]

I trust my hour meters because they are so high, nobody wants them. lol
They all do work properly though.

Same!

 

[Vetech63]

This machine don't got one.........

Oooppppps!

 

[Baxsie]

Thanks for all of your feedback.

Concerning the hour meter, I can verify that right now it it is counting up.

The wear surfaces on those track rollers are farked. You do not want to be running new track links up against those rollers

Those rollers show extreme wear…

Hate to say it, but I would change them all

Unfortunately I also am in agreement. Replacing the tracks and pads and sprockets and not replacing those rollers, is not very helpful.

Argggh. I know you are right and I hate to spend the money.

Maybe I should try Alibaba? What could go wrong?



Well, I am off to the local CAT dealer to see what my options are.

For the tensioner, the piston ( CAT 353-5584 ) appears to be nothing but a 40mm polished rod. I wonder if a hydraulic shop might be able to cut and chamfer me something for less money than the CAT part ($175) ?

 

[Vetech63]

Google the part numbers. There may be new aftermarket parts available

 

[Baxsie]

So do I need a top roller too?



Seems like that would be less critical with only the weight of the track. Way more expensive at $252 each ( CAT 333-5602 ).

The piston for the idler appears to be 40mm OD, 200mm ~ 200mm length.

Purchasing through Magister Hydraulics is $54 shipped. Tempting.

 

[Nige]

So do I need a top roller too?

You do..